Google is the one sending out the updates & not Rogers. The NEXUS line is auto updated straight from Google. Rogers has nothing to do with it another then saying the okay to Google. Also there has been a few issues with the new update from what i heard.
Nexus not Galaxy series
The Canadian ones are updated through Samsung, not Google directly. You have to root it to change the product code in order to get the google updates. 4.0.3 is not out yet.
If you bought the Galaxy Nexus thinking it was going to get the updates first and directly from Google ,I strongly suggest you flash the Google ROM on your phone.
To do so, you need to unlock the phone boot-loader (most certainly void your warranty).
This is a one-time operation that entirely wipes your phone data for (obvious) security reasons.
Official updates for Nexus devices from Google are available here: http://code.google.com/android/nexus/images.html
(4.0.3 is not available yet)
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